It’s in the cheese
Some will tell have you believe that the perfect cheese dip needs things like cornstarch or butter, but you shouldn’t listen to them. The only non-cheese ingredients you need are sodium citrate (two cups for every four cups of cheese) and water.
Choose your cheese
Though it might be tempting, don’t go with shredded cheese. Those bags you see at the supermarket usually contain additives, which are designed to stop the cheese from melting or forming clumps in the bag. Getting that would be unbelievably counterproductive for your sauce purposes. Instead of getting anything pre-shredded, just get blocks of your favorite cheese and use those arms to grate your own cheese flakes.
Don’t be an agist
The most popular nacho cheese can usually be found served in bowling alleys or stadiums. To create a similar dip, ask the cheese counter for an American cheese mix and spice it up with some blue cheese. For something a little more refined, get a few kinds of both new and old (but not too old) types of cheese. Use hard/semi-hard cheese (Camembert, Fontina, Stilton, etc.) to create a good base with good moisture levels.
Spice up your life
Stylize your cheese dip to your personal taste with spices or other flavorful elements like jalapeños. If you are into a more subtle kick, you can even use the juice the jalapeños swim in when they are still in the jar — just replace some of the water in whatever recipe you’re following with a little jalapeño juice and you’re golden.